Method of and apparatus for regulating the fuel supply to internal combustion engines



Feb. 28, 1933. H. JUNKERS 1,899,038 METHOD OF AND APPARATUS FOR REGULATING THE FUEL SUPPLY TO INTERNAL COMBUSTION ENGINES Filed Nov. 2, 1929 P1 W I I Hg, 1 I P2 7 I I I M I 200 6:00 1 000 OQ n if 257 mmatithe lower range.

5 certain speed limit Pass d Feb.28,'1933 nueo mass, or nnss'au, ennum METHOD AND APPARATUS I03 BEGULATING THE FUEL COMBUSTION ENGINES surrrnr mo Application filed November 2, 1829, Serial No. 464,393, and in Germany R member 9, 192 8.

My invention relates to method of, and

. apparatus for, regulating the fuel supply to internal combustion engines. My invention is particularly suitable for engines the speed of which varies within wide limits, for instance, motor car engines.

In such engines the power maximum as determined by the torque or mean effective pressure must be reduced as compared with the 10 amount of the torque or mean effective pressures which are permitted at a'medium speed, if the speed increases beyond this medium, as otherwise the stress the engine might cause damage or failure.

Governors as designed heretofore have the drawback "they invariably supply the maximum amount of fuel upon an increase of the load. The

i f consequence is that the fuel supply is either 2 too large for the high-speed range, or too small for the low-speed range. If the maxi mum fuel sup 1y for both speed ranges is calculatedfor t e maximum load at the wer speed range, it is too large for the higher range, and the engineis Sllb]80t6d to excessive stress when the limit of the lower range is overstepped, while, on the other han if the maximum fuel supply is calculated for the maximum load at the higher speed range, it is too small for the lower range, the limit performance of the engine is un uly reduced at this ran e, and, besides, the regulation is unnecessari y de'la ed. i

It is an ob'ect o myinvention to eliminate the drawbac s of the old regulation so that the engine will 0 rate at good eflicienc under any load an at any speed, and wi not be overstressed.

,To this end Ivary the fuel su vidually for the lowergflflifort and effect this variation while" speed range,

t e conditions requiring regulation exist, that is within the interval from the occurrence of abnormal to the re-establishment of normal conditions. The variation-is effected in such manner that the maximum fuel supply at the higher rangeis less than the maximum Means for reducini'the fuel supply from a ave already been sugsgeed is allowed to exceed the limit, and is that, irrespective of the speed,-

e higher illustratin t gested. This is effected by providing a throttling device in the suction pipe, or by making the suction pipe with an inside diameter which is smaller than that of a normal suction pipe. The suction increases with the speed and the throttling action increases also but is a function of the square of the speed. The consequence is that the throttling action only becomes effective at a speed which far exceeds the speed limit, Consequently, the

en reduced. Obviously this system involves the same defect as the governor-controlled system previously referred to, that is the amount of fuel is not only not adapted to the speed ranges, but is also regulated after, and not within, the above-said interval, in other words, the counteraction is onl started after the high speed has been attaine It is another ob'ect of my invention to provide apparatus or performing my meth-v od. To this end I provide an automatic speed regulator such as a centrifugal governor adapted to be operated b the engine, means 0 eratively connected to t e governor for regu ating the fuel supEly, means for adjusting the governor for d1 erent speeds during operation, and means operatively connected to means for reducing the regulator-adJusting the fuel supply to the engine at higher spec ranges. v

In' the drawing afiixed to this specification .and forming part thereof two governing sys tems for performing my'inve'ntion are illus-j. trated dia rammatically byway of example.

In the mining a Fig. 1 is a diagram showing torque plotted against speed for illustrating the opera- .tionaccordin to mymethod,

Fi s. 2' an 3' are diagrams showing fuel supp y-ands "eedplotted against time, and

e fuel' supply at the higher and at the ower speed' range, res actively,

Fig. 4 is a partly sectional si e elevation of the first, and e Fig. 5 a similar view of a second'system. Referring first to Fig. '1, the ordinateindicates the torque M, t e abscissa the speed n. Thesli htly curved line 1 indicates the variation 0% the torque M as a function of normal within the the speed n, if the engine is re lated for the maximum fuel supply fm igs. 2 and 3) atthe lower speed range, and the line 2 indicates the variation if the fuel suppl is regulated for the reduced maximum uel sup ly fmr, Fig. 3, at the higher speed range. If 5m supply is re lated so as to obtain the torques indicate? become too high from a given speed limit, say 600 revs. er min., corres nding to torque P If t e supply is regu ated as indicated by line 2 thelimit performance of the engine is unduly reduced at the lower speed ran since within this range the load might be increased for the difference of the torques plotted at 1 and at 2.

I the engine is regulated in accordance with my invention, the maximum fuel supply is reduced from the limit of the lower e, torque P as shown by curve 3, until at t e highest speed, 1,200 revs. per min., the torque P, is equal to that indicated by line 2 for the higher range.

Referring now to Fig. 2, f is the fuel supply, and v is the speed of the vehicle, say miles p. h. which are both plotted against time t. The dotted lines shows a speed 1; of the vehicle which is within the lower range, that is, at or below the speed corresponding to 600 revs. r min. of the engine, as shown in Fig. 1. ssume that the resistance is constant and comparatively low until the time t so that the small amount of fuel f only is required for low speed 12. -At the time t the resistance is increased, for instance, the vehicle starts climb ahill. The speed of the vehicle decreases mmediately and the governor makes up for the loss by supplying to the engine the maximum amount of fuel fm. The vehicle is s ded up and then the fuel supply is re uced from fm to f wh-ich'is more than f so that from the time t the vehicle will climb the hill at the former speed 12 but with an increased supply of fuel.

Referrinilnow to 1g. 3, V is a speed 'gher range, and F is the correspond' time t t e resistance is increased, say, bill. If

the engine were regulated manner, the maximum amount of fuel fm would be an plied, as shown by the dotted line. A ccor mg to my invention, however, the maximum fuel supply is redueed to fmr by the'governor, until at the time t'the speed V has been reestablished with the increased fuel supply F correiaflonding to the higher load, see heavy full As a rule, the time interval from t to t will be longer within the higher s ed range,

bya

Fig. 3, since only the comparatively small. is available to makeamount of fuel fmr-F' up for the reduction of speed at the beginmug of the hill while at the lower speed by line 1, the load will keeping up the larger amount of fuel. At the fr in they I 1,aee,osa

range the larger amount fm-f is available.

It will be understood that my regulation is distinguished from the normal regulation which only fixes a speed limit by cutting oil the supply of fuel at that limit, in that it fixes two distinct maxima of fuel supply, an absolute maximum fm for the lower ran e, and a reduced maximum fmr for the big er range. The maxima are attained in both cases not only if the resistance increases to the maximum which the engine is able to overcome but already during the interval tt' during which the conditions requiring regulation exist. This includes the cases where the automatic regulating a paratus s a spring w ich is held between a movable spring plate 17 and a ball bearing 18 in the overnor casing, 19 is a bracket projecting rom both sides of the shaft 16, 21, 21 are pivots at the ends of the bracket, and 22, 22

are weighted levers which are mounted to rock about the pivots 21 while their inner ends are connected to a sleeve 23 in the governor casing by links 24. 3 is the governor sleeve, and 4 is an angle lever operatively connected with the sleeve and transmitting the stroke of the sleeve to a rod 5.

This rod is here provided near its end with a rack 6 meshing with a pinion 7, which acts on the regulating member proper, for instance a throttle 1n the mixture suction conduit of a carbureter engine or a device for varying the effective stroke of a fuel pump in the case of a solid injection engine. For thg purpose of adjusting the governor for di be varied. This may be done b means of an angle lever 10, against one on of which the es and of the spring abuts by the late 17 and which can be adjusted from a l lever 11 by means of a rod 12. With this end is connected another rod 13, the end of which carries the sto 14 faced by a check 15 on the rod 5. en the governor is adjusted for low speeds, as shown in full lines, the

distance between the stop 14 and check 15 is such that the governor is entirely free to operate, so that with an increased load it can adjust the regulating member for the highest possible supp y of fuel fm or fmr. However, if the spring 2 12, 13 being shifted to this end into the position shown in solid lines, the stop 14 will also be shifted towards the check 15 and in consequence thereof, when the load increases, the governor will figures 95 erent speeds the tension of spring 2 can "9 is further compressed, the rods not be able any more displace. the rod 5 and the regulating member governed by it for the highest possible supply of fuel, but only so far until the check 15 meets the stop 14. Obviously this limitation of the governor stroke will occur the sooner, the more lever 11 is displaced in the direction towards an increase of the speeds of the engine.

The arrangement shown in Fig. 5 is similar to the one above described, only the stop 14 is here replaced by a stopQ at the end of a third arm of the angle lever 10' acting on the spring, while the check 15-is here replaced by a part, such as the projecting rim 25, which reciprocates together with the governor itself, this part cooperating with the stop 24 in such manner that, when the governor is adjusted for high speeds, the governor body can move downwardly only until it meets this stop. Here again I obtain that within the range of higher speeds the maximum quantity of fuel supplied will be less than within the range of smaller speeds.

The devices or systems illustrated in Figs.- 4 and 5 are substantially similar to the regulating device for engines shown and described in my patent of the United States, No. 1,841,897 dated January 19, 1932, but in this patent I have shown a double-armed leverintermediate the rod which is connected to the lever 11 and the check and therefore the operation is reversed as compared with the operation of the present subject matter. As compared with the apparatus illustrated in Fig. 5, the device according to my said patent limits the stroke of the governor only at slow displacement of the system for regulating the speed of the governor, and particularly at low speed ranges, the object being to increase the speed smoothly and without jerks. Thus, while in the device according to my said'prior patent the fuel supply is increased with in. creasing speed, in my present invention it is reduced for speed ranges beyond a certain medium speed.

I wish it to be'understood that I do not desire to be limited to the exact details of construction shown and described for obvious modifications will occur to a person skilled in the art.

In the claims aflixed to this specificationno selection of any particular modification of the. invention is intended to the exclusion of other modifications thereof and the right to subsequently make claim to any modification not covered by these claims is expressly reserved.

I claim 1. The method of regulating automatically the fuel supply to internal combustion en gines in conformity with the speed of the engine comprising varying-the fuel supply while theconditions requiring regulation exist by reducing the maximum fuel supply for speeds above a certain limit as compared with the maximum supply below such limit.

2. An apparatus for regulating the fuel supply to internal combustion engines comprising an automatic speed regulator adapted to be operated by the engine, means operatively connected to said regulator for regulating the fuel supply to the engine, means for adjusting the regulator for different speeds during operation, and means operatively connected to said regulator-adjusting means for reducing the fuel supply for higher speed-ranges.

3. An apparatus for regulating the fuel supply to internal combustion engines comprising an automatic speed regulator adapted to be operated by the engine, means operatively connected to said regulator for regulating the fuel supply to the engine, means for adjusting the regulator for various speeds during operation, a stop operatively connected to said supply-regulating means, and a dog adapted to engage directly with said stop and so connected to said regulator-adjusting means that the distance between the stop and the dog is reduced when said adjusting means move in the direction corresponding to higher speed ranges. y

In testimony whereof I a'lfix my signature.

HUGO J UNKERS. 

